QTL Mapping For Common Wheat SRC And The Relationship With Processing Quality

Solvent retention capacity (SRC) is one of important quality traits in soft wheat quality evaluation and breeding program. Exploring the QTL related to SRC was useful to gene clone and marker-assisted selection(MAS). A RIL population originated from Ning 7840×Clark was used to detect the SRC QTLs, and the association between SRC and other quality traits was analysised. The main results wre as follows.1. Two hundred and eighty-two SSR markers and 486 AFLP marker were used to constructed the genetic maps. The total length of linkage maps was 1384.9 cM, and the average distance is 1.8 cM from marker to marker. QTLs related to flour protein content and flour yield were detected on chromosome 4B, which can accounting for 27.5% and 12.5% of the phenotypic variance, respectively, and the two QTLs located at the same location. One major QTL was detected for kernel hardness on chromosome 5D (Xcfd18-XGWM190), which can explain 88.2% phenotypic variance and might be Ha gene. One QTL related to Water SRC was also detected on chromosome 5D. Two QTLs for lactic acid SRC were detected on chromosome 6D and 5D with -5.4 and 4.7 for additive effect, respectively, and accounting for 15.2% and 11.5% of the phenotypic variance, respectively. The QTL for sodium carbonate SRC was detected on chromosome 4D and located between XAGC.CTC7-XWMC720 with 1.4 for additive effect, and explaining 12.2% of the phenotypic variance. Two QTLs for sucrose SRC were detected on chromsome 5D and 5A with -2.84 and - 2.71 for additive effect, respectively, and accounting for 15.9% and 9.9% of the phenotypic variance, respectively. One QTL on 5D was similar to hardness and water SRC, and the other on chromosome 5A was located between XWMC705-XAGC.CTC6.2. Significantly association was observed among four SRCs, and between SRC and others quality traits. Sucorse SRC was significantly correlated with sodium carbonate SRC and lactic acid SRC with r = 0.57 and 0.62, P<0.01, respectively; correlated with hardness with r = -0.57, P<0.01; correlated with kernel protein content with 0.27, P<0.05. Sodium carbonate SRC was correlated with lactic acid SRC and flour yield with r = 0.40 and -0.24, P<0.01 and 0.05, respectively. Lactic acid SRC was significantly correlated with kernel protein content and hardness with r = 0.23 and 0.27, P<0.05. The higher lactic acid SRC was presented in non-1B.1R lines than 1B.1R translocation lines. Highly and positively correlation was observed between lactic acid SRC and Zeleny sedimentation volume with r = 0.85, P<0.001, so the lactic acid SRC can be a good reflection of the quality of gluten.The hardness and sedimentation value of the type of high-protein content were significantly higher than the types of low and middle protein content. The hardness value of the three kinds of protein content type was significantly different, but the lactic acid SRC was not significant differences among the three kinds of protein content type.The difference was presented in the different type hardness, but the degree was different. A larger variation of protein content, lactic acid SRC and the sedimentation value was presented in different wheat varieties, with the positive relationship with the grain hardness.